如何通过输入ID号使python GUI在弹出窗口中显示信息？ 还有错误消息？

Question

这是我到目前为止的代码。 最后，输入学生证后，我很难弄清楚如何制作一个弹出窗口，说“等级为[A]”。 如果输入了错误的ID，我也不知道如何创建一个弹出窗口，显示“找不到学生ID”。 我在遇到问题的部分加上星号。 谢谢！

from Tkinter import *
import tkFont
import tkMessageBox

students = {}

class studentDB :
    def __init__(self) :  # Constructor
        # Sets attributes "studentID", "lastName", "firstName"; sets attribute "scores" as empty list
        global students
        students[1000] = student(1000, 'abc', (92, 95, 97))
        students[1001] = student(1001, 'def', (84, 91, 77))

class student :
    def __init__(self, sid, passwd, scoreList) :  # Constructor
        # Sets attributes "studentID", "lastName", "firstName"; sets attribute "scores" as empty list
        self.studentID = sid
        self.passwd = passwd
        self.scores = scoreList

    def getPassword(self) :  # Returns the student ID
        # Returns attribute "studentID"
        return(self.passwd)

    def computeAverage(self) :  # Computes & returns the total score
        # Computes & returns totalScore of list attribute "scores"
        totalScore = 0
        for val in self.scores :
            totalScore = totalScore + val
        return(totalScore/float(len(self.scores)))

def getGrade(score) :
    if (score >= 90) :
        return 'A'
    elif (score >= 80) :
        return 'B'
    elif (score >= 70) :
        return 'C'
    elif (score >= 60) :
        return 'D'
    else :
        return 'F'      

class myApp :
    def __init__(self, top) :
        # Creates a window with:
        #    Label and text box for "Student's ID";
        #    Button labeled "Get Grade" to get the grade for the student; and
        #    Button labeled "Quit" to quit the application
        # You must write the rest of the myApp constructor, here.
        self.root = top
        self.bframe = Frame(self.root)  # Create a container Frame at the bottom
        self.bframe.pack(side=BOTTOM)
        self.xlabel = Label(self.root, text="Student ID")  # Create Label
        self.xlabel.pack(side=LEFT)
        self.xentry = Entry(self.root, bd=5)  # Create Entry box
        self.xentry.pack(side=LEFT)
        self.xentry.focus_set()  # Set focus in Entry box
        self.xopen = Button(self.root, text="Get Grade", command=self.showGrade) # Create open Button
        self.xopen.pack(side=LEFT)
        self.xquit = Button(self.bframe, text="Quit", command=self.quitit) # Create quit Button
        self.xquit.pack(side=BOTTOM)


    def showGrade(self) :
        # Creates either:
        #    Warning message if SID is not found or
        #    Information messaged with grade
        global students
    # You must write the rest of the showGrade method, here.
        **sid = self.xentry.get()
        if 
        import tkMessageBox**

    def quitit(self) :
        # Handler for Quit button click
        self.root.destroy()
        return
# End of myApp class

studentDB()
top = Tk()
app = myApp(top)
top.mainloop()

Answer 1

以下是我使用的python 3。 它应该给你的想法。 我相信代码与python 2非常相似，但有一些小的更改。

# import the messagebox dialogs
from tkinter import messagebox

# these will be in the showGrade method
# to show the sid and grade in a message box
messagebox.showinfo('Student Results', 'SID:{0} Grade:{1}'.format(sid, grade))

# to show that sid not found
messagebox.showerror('Error', 'SID:{0} not found'.format(sid))

消息框方法显示一个弹出窗口，用户单击“确定”按钮

Answer 2

您可以尝试在按下按钮时创建新的GUI，请参阅：

def showGrade(self) :
    # Creates either:
    #    Warning message if SID is not found or
    #    Information messaged with grade
    global students

    sid = self.xentry.get() #gets entered studentID

    ##CREATE GUI##
    gradewindow = Toplevel()

    gradelbl = Label(gradewindow)
    gradelbl.pack()

    ##END CREATION##

    try:
            grade = #get grade associated with entered studentID
    except ValueError:
            gradelbl.config(text="Student doesn't exist!")
    else:
            gradelbl.config(text=grade)

    gradewindow.update()

请注意，您自己将不得不重新获得相关的成绩，我对字典结构没有经验，所以我会把它留给您。

这是它的工作方式：

1. 检索用户输入的sid值。
2. 定义并创建了新的GUI
3. 此后，程序立即检查获取的成绩，如果字典中不存在该成绩，它将返回ValueError，该值将被排除，并在新窗口中显示错误。
4. 但是，如果找到它，则GUI将显示它。

希望这会有所帮助。